Mistdancer

Those rogues that have been born with, developed or bargained for a connection to the Mists of Ravenloft have gained a minor control of their strange properties. These rogues dance in and out of reality in a burst of mist, allowing them to get the drop on opponents. They can also summon the mist to aid them, allowing them to sneak past the most vigilante guards or gather whispers from the wind itself. The strongest have even been known to drag unwitting creatures into the mists them selves.

Mist dancer tend towards pale skin and hair, looking almost albino at higher levels. Their eyes are always grey and seem to be swirls mists rather than solid colour.

Dance of the Mists

The mistdancer is able to step through the mist a short distance, allowing them to be in the best position to strike at all times. 

As a bonus action the rogue may move up to 30 feet (as per misty step). If he appears out of a character or creatures line of sight they are not aware of his location as this makes no sound.

This ability may be used once per proficiency bonus. All uses are regain at the end of a short or long rest.

Cloak of the mists

Get +2 AC and double prof bonus to attacks after using dance of mists.

Misty aid

As an action can call mists to give adv on Stealth checks or perception and investigation checks as mist obscures or seeks out information. This lasts for 1 minute.
Using this feature uses one use of dance of the mists.

Horror of the mist

Upon a successful sneak attack the mistdancer can drag their opponent through the mists. They can take them up to 60 feet in any direction. The horrors of the mist grab at the minds of the recepient of this trip causing them to take 4d6 psychic damage and be frightened. A successful wis save will half the DMG and they will not be frightened.

This ability can be used once and this is regained after a short or long rest.